EM3 (EM3) tube replacement.

Dear collectors,

Which would be a reasonable tube replacement for the EM3, ideally with the same P8A base socket?

Thanks in advance, Bruno.

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Hello Bruno,

the easiest substitution of the EM3 is the EM1. It has the same P8A base and even the same base diagram, so a direct replacement is possible.

But the EM1 has some disadvantages:

• it's almost the same way unavailable as the EM3

• it can handle only small AGC voltages up to -5 volts for full display. This means, for any stronger receiving signals, no change on the indication pattern will happen.

The next better substitution of the EM3 is the EM4, which also has a P8A base. The situation about the EM4 is:

• it's also scarce to get

• since it has 2 indication sections, it can handle week and strong signals as well, without any problems.

• it requires some alteration in the base wiring: since the EM4 has 2 anodes, a second 1 meg ohm resistor has to be connected between a2 and L according to the EM4 base diagram.

   

Good luck with your EM3 replacement,

Best Regards, Jacob

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Hello Jacob,

Thanks by your kind and supported answer. 

I am restoring a Philips 289A Export model for the Indies.  Fortunately I have the EM1 and EM4 NOS and I have determined to adapt the EM4 because the PH 289A has RF amp stage, four bands and two wide band , then it should be an interesting complex radio with good behavior in short wave reception. 

As usual you have been very kind again and I am very thanked. 

Best regards, Bruno.

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